Saturday, July 10

Newfangled Brakes

V Brakes Get Clogged With One Trip Through the Mud Pit!
Buddy, my Specialized Tricross, came with V Brakes (technically, they're "direct pull cantilever brakes" since V Brake is a Shimano Trademark). If you have a mountain bike, you may have them as well. I kind of liked the idea, knowing how strong V Brakes are, and not realizing that Specialized was actually letting their marketing people foist off a benighted and poorly engineered product off on unsuspecting public. You see, they coupled these excellent brakes with even better brake levers, the SRAM Rival. This is unfortunate because that combination is much like attempting to carry the racehorse Seabiscuit in a Jaguar XJ220. Both are among the very best, but they just don't go together. The V Brake has a LOT of mechanical advantage for the pads. With enough cable pull, you can bend your rims if that is what is needed to stop. The SRAM road brakes, on the other hand, do not pull very much cable. They're designed for fine modulation of the brakes at speed. What this means is that I run with virtually no pad clearance, so that I have brakes before the levers bottom out on the bars. In their wisdom, Specialized did not include any barrel adjusters in the system, making the monthly brake fine tuning even MORE fun (he says sarcastically). This was not just on their low end bikes, either. The S Works bike was set up exactly the same way.

At left, you can see how the brakes look after a few cross laps, when initially properly adjusted, so that you actually HAVE a token braking capability. I did not add any debris for added drama. It wasn't necessary.

There is a very good discussion on cyclocross brakes, here. You'll note that one team DOES use V brakes in competition. They combine their use with a little gadget called a "Travel Agent." The Travel Agent allows you to double the cable pull, allowing those massive V Brake pads to work with a reasonable amount of clearance using the amount of cable pull that is possible from road levers. This raises a couple of questions. First, if this is such a good idea, why didn't Specialized just do it themselves rather than making owners have to buy obscure items the LBS hasn't heard of to make the brakes work properly? Second, those pulleys rub the cable, leading to at least one report of a brake cable snapping. Am I fooling myself by making my brakes fail completely when I will need them most?

I'm going to try out the Travel Agent. I'll just keep a careful eye on the cable for signs of fraying. Conveniently, I already have one that I bought to jigger the shifters on Frankenbike, and my LBS now knows how to get them.

Still, I like to keep a step ahead of my brakes instead of adding to my list of ways the "B" in "ABC Quick Check" can snag a cyclist. When I took Buddy in for its 5000 mile overhaul, I had the mechanic add a cantilever brake hanger at the front. The bike already had one in back which I use as a supplemental fender support. Unfortunately, clearance between the hanger and the stem is very tight. There's about a finger's width clearance between the top of the hanger and the stem. Hmm. Durn newfangled bike stuff! I would have thought they'd get this stuff ironed out with nearly 200 years of experience.

Front Cantilever Brake Hanger is Very Tight - Yes, the "Specialized" Printing is Upside Down on the Bike

Rear Canti Brake Hanger
BY THE WAY, Specialized has now abandoned this approach in their new Tricrosses and they have gone back to cantilever brakes just like almost all other cyclocross bikes. Any you see at your LBS this way are old models you might get a good deal on. Just figure out how you're going to make the brakes work BEFORE you take it home!

Lest I come across as negative, please know that these are the strongest brakes I've ever had. I LIKE strong brakes. And they stay that way for at least a couple of weeks of heavy use, before they need to be adjusted again.

Comments can be the best part of these posts. I tried the travel agent on the front brake and I can't say I'm impressed. OTOH, I now have one of the bad boys below on order. I think I'll get a set of Tektro CR720 Cantis and we'll see how THOSE work. What can I say? I just want brakes, even if Specialized thinks I don't need more than the appearance of brakes.


John Romeo Alpha said...

I've seen Travel Agents on brakes but haven't ridden one for any length of time. I was surprised to see essentially the opposite type of device on a bike I rode last week, something called a "Shimano Power Modulator" hanging on the front noodle, which REDUCES the force of the front v-brake. Sheldon Brown wrote about them and said they were no good, which is good enough for me. Made the front just feel mushy.

Chuck Davis said...

Tektro makes a fork crown hanger that can allow a smoother cable/casing run to the front brakes with room for an in line adjuster

Chuck Davis, Tulsa

Steve A said...

Interestingly, prompted by Chuck's comment, it turns out Specialized also offers a fork crown hanger specially designed for the Tricross. I don't know if it's available in the US or only in Canada.

Tracy W said...

We've got V brakes on our tandem, and have the same situation with our Shimano 105 STI levers. Those suckers are exactly what you need for the tandem. They can stop you on a dime, but after 5 years of riding it, I still don't like the fact that the lever nearly bottoms out to achieve that degree of stopping power. You've got to run those things with almost zero clearance, which means that they require a lot more love and attention than the road brakes on my Giant and the cantilever brakes on my Surley.

We've got friends who use a travel agent on their front brake and I've never known them to have cable problems from it. They're actually a pretty common sight to see on tandems where a little extra stopping power is often a desired feature.

Steve A said...

Tracy, the Travel Agent effectively trades power for pad clearance. I didn't really like the feel. I'm hopeful I can get a better combination with low profile cantis that use V Brake pads. Specifically Tektro CR720 which have excellent reviews and cost $40 for F&R. My current Kool Stop pads should work. I'll plan on some comparison. I'd like to get things done before August when the Tricross becomes a daily rider again.

Apertome said...

You can get different brake levers that are v-brake compatible. Probably doesn't help if you have brifters.

My Long Haul Trucker came with Tektro Oryx canti brakes. They're cheaper than the CR720s, but don't be tempted, they're weak. I hope to upgrade them someday.

Chuck Davis said...

Hoping knot digress too much, the flika link shows the Tektro hanger on a small Pake C'mute
and a forged dropped IRD hanger on my Soma Saga

Re Oryx and complaints, I've herd'um before...

I've got std Oryx on the Saga and my DoubleCross and I certainly don't need to stop any better

The Pake has Origin8 Tektro Oryx that fit onto the bosses better that the std Oryx

Chuck Davis, Tulsa

Khal said...

We have Shimano 105 STI levers, Travel Agents, and LX linear pull brakes with parallel-push linkage on our Co-Motion Primera. We got the long bike with Avid Single Digit 5's and they were terrible so I swapped out the LX brakes from our old tandem for some improvement.

Yes, you trade clearance for power and I am not impressed. One of these days I'll fix up the tandem with disk brakes or just move to the flatlands.

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